Re: ion chamber vs GM

["Mike Malaxos" <rss@arach.net.au>]

The most sensitive instrument for detecting this energy (assuming 40 -
200keV) may  be a scintillometer with 10 mm to 100 thick 50 mm diameter
sodium xtal. If the radiation may be via narrow beams it is the most
suitable instrument. 

If the the energy range is wide a thin window Ion Chamber such as an
Eberline RO2  or Ludlum 9 with the slide open must be used to make a
measurement of dose rate. For this measurement the beam must totally
enclose the chamber. If it does not the measuremnt is meaningless.

Best Regards
M.Malaxos
Radiation Safety Services
69-71 Robinson Avenue Belmont
Western Australia.  6104 
Fax 61 89 475 0165
P 61 89 475 0099  a/h 089 255 1214
email rss@arach.net.au
 

----------
> From: michele.smith@amd.com
> To: Multiple recipients of list <radsafe@romulus.ehs.uiuc.edu>
> Subject: ion chamber vs GM
> Date: Friday, 6 March 1998 22:40
> 
> I work with tools that can produce low energy x-rays incidentally.  I
> am currently using an ion chamber to do my testing of these tools.  I
> was told that a GM would not be sensitive enough to pick up the low
levels
> that I would have.  Can someone tell me what the guidelines are for
determining
> which instrument is preferred?  I am dealing with beam currents generally
> less than 200 KeV (if that helps any).
> 
> Michele Smith
> michele.smith@amd.com